It has been discovered that NMDA receptors, and particularly the NR2B sub-unit, play a critical role in many types of pathologies with a neuron origin. Stimulation of these receptors provokes neurone apoptosis, and consequently induces neuro-degenerative diseases. These receptors are also involved in perception of pain (see J. M. Loftis, A. Janowsky/Pharmacology & Therapeutics 97 (2003) 55-85).
However, the clinical use of NMDA receptor antagonists is of very limited interest due to the fact that they induce psychotomimetic side effects (hallucinations, mnestic and learning disorders, psychomotor disorders, etc.).